uTorrent destroys my connection. It works well, but I have a VoIP service, and my phone quality drops to hell when I have uTorrent running. It's almost irrespective of the speed the thing is going at (20kB/s up is less than half my u/l speed, but it destroys phone quality regardless). You might think this is going to be a problem for all clients, but BitTornado, the client I switched back to after trying uTorrent, keeps torrents at 25-30kB/s up with no discernible phone quality loss.